微信小程序调用wx.requestPayment后，只有第一次能够弹出微信支付二维码，之后每次支付直接提示支付失败，这是什么原因，控制台报以下错误：parameter.timeStamp should be String instead of Undefined;parameter.nonceStr should be String instead of Undefined;parameter.package should be String instead of Undefined;parameter.signType should be String instead of Undefined;parameter.paySign should be String instead of Undefined;"constructor: (...)